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船用中速柴油机的进气门早关米勒循环

Journal of Marine Science and Application 2022年第1期21卷 151-160页

作者：魏胜利吴成成严书哲丁统元陈洁 School of Automotive and Traffic Engineering Jiangsu UniversityZhenjiang 212013China

In this study,a one-dimensional simulation was performed to evaluate the performance of in-cylinder combustion to control NO_(x) emissions on a four-stroke,six-cylinder marine medium-speed diesel engine.Reducing the combustion temperature is an important in-cylinder measure to decrease NO_(x) emissions of marine diesel engines.The Miller cycle is an effective method used to reduce the maximum combustion temperature in a cylinder and accordingly decrease NO_(x) emissions.Therefore,the authors of this study designed seven different early intake valve closing(EIVC)Miller cycles for the original engine,and analyzed the cycle effects on combustions and emissions in high-load conditions.The results indicate that the temperature in the cylinder was significantly reduced,whereas fuel consumption was almost unchanged.When the IVC was properly advanced,the ignition delay period increased and the premixed combustion accelerated,but the in-cylinder average pressure,temperature and NO_(x) emissions in the cylinder were lower than the original engine.However,closing the intake valve too early led to high fuel consumption.In addition,the NO_(x) emissions,in-cylinder temperature,and heat release rate remarkably increased.Therefore,the optimal timing of the EIVC varied with different loads.The higher the load was,the earlier the best advance angle appeared.Therefore,the Miller cycle is an effective method for in-engine NO_(x) purification and does not entail significant cost.

关键词： Medium-speed diesel engine Miller cycle Combustion NO_(x)emission Early intake valve closing(EIVC)

Chiral selective effects of doxazosin enantiomers on blood pressure and urinary bladder pressure in anesthetized rats

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Acta Pharmacologica Sinica 2006年第11期27卷 1423-1430页

作者： Shi-ping MA~2 Lei-ming REN~(2,4)ding ZHAO~2 zhong-ning ZHU~2 Miao WANG~2 Hai-gang LU~3 Li-hua DUAN~3 2 Hebei Medical University School of Pharmacy,Shijiazhuang 050017,China 3 Hebei Professional College in Chemical & Pharmaceutical Sciences,Shijiazhuang 050031,China Hebei Medical University School of Pharmacy Shijiazhuang China Hebei Professional College in Chemical & Pharmaceutical Sciences Shijiazhuang China

Aim:To study chiral selective effects of doxazosin enantiomers on blood pres-sure and urinary bladder pressure in anesthetized rats.Methods:In anesthetizedrats,the carotid blood pressure,left ventricular pressure of the heart and theurinary bladder pressure were recorded.Results:Administration of S-doxazosinat 0.25,2.5,25,and 250 nmol/kg iv produced a dose-dependent decrease in bloodpressure,but its depressor effect was significantly weaker than that induced byR-doxazosin and racemic-doxazosin(rac-doxazosin),and the ED30values(producinga 30% decrease in mean arterial pressure)of R-doxazosin,rac-doxazosin and S-doxazosin were 15.64,45.93,and 128.81,respectively.Rac-doxazosin and its enan-tiomers administered cumulatively in anesthetized rats induced a dose-dependentdecrease in the left ventricular systolic pressure and ±dp/dtmax,and the potencyorder of the 3 agents was R-doxazosin>rac-doxazosin>S-doxazosin.Rac-doxazosinand its enantiomers decreased the vesical micturition pressure dose-dependentlyat 2.5,25,and 250 nmol/kg,and the inhibitory potency among the 3 agents was notsignificantly different.Conclusion:S-doxazosin decreases the carotid blood pres-sure and left ventricular pressure of the heart less than R-doxazosin and rac-doxazosin,but its effect on the vesical micturition pressure is similar to R-doxazosinand rac-doxazosin,indicating that S-doxazosin has chiral selectivity between car-diovascular system and urinary system in anesthetized rats.

关键词： R-doxazosin S-doxazosin blood pressure ventricular pressure urinary bladder pressure rat

海绵城市年径流污染总量削减率定义及计算方式探讨

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中国给水排水 2023年第24期39卷 93-99页

作者：苏定江刘希董佳蔡岚毛绪昱刘杰重庆市市政设计研究院有限公司重庆400030 重庆市海绵城市建设工程技术研究中心重庆400030

年径流污染总量削减率是我国海绵城市建设基本控制指标之一,从工程设计可行角度探讨了其存在的狭义和广义两种定义。狭义年径流污染总量削减率为雨水设施对已形成的径流中污染物去除比例,计算所需参数可通过现有标准取值,但采用“1-雨... 详细信息

年径流污染总量削减率是我国海绵城市建设基本控制指标之一,从工程设计可行角度探讨了其存在的狭义和广义两种定义。狭义年径流污染总量削减率为雨水设施对已形成的径流中污染物去除比例,计算所需参数可通过现有标准取值,但采用“1-雨量径流系数”作为年径流总量控制率时不适用于该计算方式。广义年径流污染总量削减率为低影响开发模式下外排径流污染物减少比例,计算所需参数不能通过现有的标准取值,因此提出了近似计算方式。广义年径流污染总量削减率可以体现透水下垫面对径流污染的去除效果,现阶段工程设计中推荐采用广义年径流污染总量削减率定义及其近似计算方式。

关键词：海绵城市年径流污染总量削减率计算方式低影响开发

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基于CAN总线的船舶机舱延伸报警系统

江苏大学学报（自然科学版） 2012年第3期33卷 316-321页

作者：仲伟波丁修方江苏科技大学电子信息学院江苏镇江212003

为了实时监控舰船机舱环境和设备运行状态,提高延伸报警的可靠性和稳定性,基于NXPLPC1766及CAN总线实现了一个舰船机舱自动延伸报警系统.系统采用集散控制方式和双主控热备冗余结构,具有良好的人机接口;采用模块化思想进行软件设计,实... 详细信息

为了实时监控舰船机舱环境和设备运行状态,提高延伸报警的可靠性和稳定性,基于NXPLPC1766及CAN总线实现了一个舰船机舱自动延伸报警系统.系统采用集散控制方式和双主控热备冗余结构,具有良好的人机接口;采用模块化思想进行软件设计,实现了主控人工、自动切换,系统运行状态自我监测,运行参数设置和多种形式的声光报警等功能;给出了系统硬件结构、软件结构:并对系统进行功能测试、可靠性测试和环境适应性测试,且将系统成功应用于多条船舶中.结果表明:该系统能够实时侦听多路报警信号并按预设规则进行声光报警,且功能完善、结构简单,能够满足现代舰船机舱自动监控与延伸报警要求.

关键词：机舱自动化自动延伸报警 CAN总线集散控制热备冗余

Reactivities of Shenfu Chars Toward Gasification with Carbon Dioxide

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Journal of China University of Mining and Technology 2007年第2期17卷 197-200页

作者： ZHANG Jia-wei ZONG Zhi-min WANG Tao-xia XIE Rui-lun ding Ming-jie CAI Ke-ying HUANG Yao-guo GAO Jin-sheng WU You-qing WEI Xian-yong School of Chemical Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China Luohe Occupation Technical College Luohe Henan 462000 China College of Resource and Environmental Engineering East China University of Science and Technology Shanghai 200237 China

Five Shenfu char samples were prepared from Shenfu raw coal at different temperatures (950,1100,1200,1300 and 1400 ℃) using a muffle furnace. Demineralization of the char samples was performed by treating them with 10% nitric acid for 10 min in a CEM Discover microwave reactor. The gasification of the chars,and corresponding demineralized chars,in a carbon dioxide (CO2) atmosphere was conducted in a Netzsch STA 409C131F tempera-ture-programmed thermogravimetry apparatus. The effects of charring temperature and demineralization on the gasi-fication reactivity of chars were systematically investigated. The results show that a char formed at a lower tempera-ture is more reactive except for demineralized char formed at 1100 ℃,which is less reactive than char formed at 1200 ℃. Demineralization decreases the char reactivities toward gasification with CO2 to a small extent.

关键词：二氧化碳气化热重分析法活性去矿化

焊接温度对5A06铝合金SPS钎焊接头组织和性能的影响

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稀有金属材料与工程 2023年第10期52卷 3461-3469页

作者：宋奎晶季雨凯韦勇丁子恒张铭雨刘鑫泉钟志宏方坤合肥工业大学材料科学与工程学院安徽合肥230009 中国电子科技集团公司第三十八研究所安徽合肥230088

5A06铝合金具有中高强度、优良的耐腐蚀性以及良好的导热和机械加工性能,在雷达液冷组件和波导结构件等精密制造领域广泛应用。本研究采用Al-20Cu-5Si-2Ni钎料,通过放电等离子烧结(sparkplasmasintering,SPS)技术实现5A06铝合金SPS钎焊... 详细信息

5A06铝合金具有中高强度、优良的耐腐蚀性以及良好的导热和机械加工性能,在雷达液冷组件和波导结构件等精密制造领域广泛应用。本研究采用Al-20Cu-5Si-2Ni钎料,通过放电等离子烧结(sparkplasmasintering,SPS)技术实现5A06铝合金SPS钎焊,研究了焊接温度对连接接头组织和性能的影响。当焊接温度为510~530℃,压力为4MPa,保温时间为10min时,接头抗拉强度随温度升高而增大,最大接头抗拉强度为152MPa,530℃焊接温度下获得的接头拉伸断口呈现韧性断裂特征,韧窝细小均匀。在低温钎料、焊接压力、脉冲电场和短时保温的综合作用下,SPS钎缝相比常规真空钎焊变窄,界面焊合率提高,晶粒细小,脆性相分散,元素扩散充分,形成的细小Mg_(2)Si和Si颗粒能够显著提升接头力学性能。

关键词： 5A06铝合金 SPS钎焊焊接温度显微组织力学性能

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细菌微机器人的研究进展

中国医学科学院学报 2016年第4期38卷 453-457页

作者：梁耀杰孙君重中国人民解放军总医院第一附属医院干部三科北京100048

细菌微机器人概念一经提出,就受到了广大科研工作者的重视,成为近年多学科交叉研究的热点。其中对于恶性肿瘤的早诊早治以及降低化疗的不良反应等方面展示了其独特的优势和巨大的应用潜力。本文结合国内外研究,拟就细菌机器人的概念、... 详细信息

细菌微机器人概念一经提出,就受到了广大科研工作者的重视,成为近年多学科交叉研究的热点。其中对于恶性肿瘤的早诊早治以及降低化疗的不良反应等方面展示了其独特的优势和巨大的应用潜力。本文结合国内外研究,拟就细菌机器人的概念、构造和医学应用进行综述,旨在拓展其医疗用途,造福肿瘤患者。

关键词：细菌微机器人趋化性趋磁性靶向性肿瘤早诊早治

Exploring diversity of different classificatory human tandem repeats

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Journal of Biomedical Science and Engineering 2008年第2期1卷 127-132页

作者： zhong-Yu Liu Xu-Feng Li Xian-Ping ding Bo Liu Yi Yang College of Life Sciences Sichuan University

Tandem repeats (TRs) are associated with dis-ease genes, play an important role in evolution and are important in genomic organization and function. Much research has been done on de-scriptions of properties of tandem repeats, such as copy-number, period, etc, and correlation be-tween mutations within tandem repeats and dis-ease. This project aims to detect some differ-ences which may exist within the features of dif-ferent tandem repeats associated with disease in human whole-genome. The features of tandem repeats associated with diabetes genes were compared to the counterparts of non-diabetes disease genes.

关键词： Diversity of different classificatory Human tandem repeats

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双动力系统燃料电池客车经济性优化设计

同济大学学报（自然科学版） 2008年第9期36卷 1246-1249页

作者：姚杰钟再敏孙泽昌同济大学汽车学院新能源工程中心

以燃料电池大客车为研究对象,根据其经济性、可靠性以及低成本的需求,提出了一种包含两套独立的燃料电池、直流/直流变换器及电机的双驱动动力系统结构形式.该结构在通过动力系统的冗余设计提高整车可靠性的同时,为进一步提高整车经济... 详细信息

以燃料电池大客车为研究对象,根据其经济性、可靠性以及低成本的需求,提出了一种包含两套独立的燃料电池、直流/直流变换器及电机的双驱动动力系统结构形式.该结构在通过动力系统的冗余设计提高整车可靠性的同时,为进一步提高整车经济性的控制方法提供了更为广阔的空间.在此基础上,采用了遗传算法的优化方法,提出了一种双电机转矩优化分配控制策略,并通过路况实验验证了控制策略的有效性.

关键词：燃料电池客车双动力系统转矩优化